100Base-T4 uses all four pairs. 100Base-TX only uses two pairs.
 (at the network interface cards/hubs)
 (at the network interface cards/hubs)
 (at the cables)
 (at the cables)
RJ45 FEMALE CONNECTOR at the network interface cards/hubs.
RJ45 MALE CONNECTOR at the cables.
| Pin | Name | Description | 
|---|---|---|
| 1 | TX_D1+ | Tranceive Data+ | 
| 2 | TX_D1- | Tranceive Data- | 
| 3 | RX_D2+ | Receive Data+ | 
| 4 | BI_D3+ | Bi-directional Data+ | 
| 5 | BI_D3- | Bi-directional Data- | 
| 6 | RX_D2- | Receive Data- | 
| 7 | BI_D4+ | Bi-directional Data+ | 
| 8 | BI_D4- | Bi-directional Data- | 
Note: TX & RX are swapped on Hub's. Don't know about Bi-directional data.
| Contributor: | Joakim Ögren, Kim Scholte | 
| Source: | ? | 
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  Document last modified: 2002-01-10